Contract Law is one of the seven pillars of foundation in law. Which is why is it important to get a grasp on it early on.

Without contract laws it would be very difficult to do any business. Companies would have to pay large sums of money because nobody trusts each other. People would only do business with people they knew very well. We would not get very much done. A contract allows each party a way to do business. A legally binding document for all parties to meet there obligations.

Contracts are used in all areas of society for the transfer of goods, letters of loan, payments, employment etc. It could be summarised in the expression "the one fact of human existence is contracts".

Contracts are controlled (mostly) by 2 sorts of legal systems:

Civil and common law system

The difference explained between them below is from Wikipedia

“Civil law or Romano-Germanic law or Continental law is the predominant system of law in the world. Civil law as a legal system is often compared with common law. The main difference that is usually drawn between the two systems is that common law draws abstract rules from specific cases, whereas civil law starts with abstract rules, which judges must then apply to the various cases before them.

Civil law has its roots in Roman law, Canon law (Christian, especially Catholic law) and the Enlightenment, alongside influences from other religious laws such as Islamic law.^[1][2][3] The legal systems in many civil law countries are based around one or several codes of law, which set out the main principles that guide the law. The most famous example is perhaps the French Civil Code, although the German Bürgerliches Gesetzbuch (or BGB) and the Swiss Civil Code are also landmark events in the history of civil law. The civil law systems of Scotland and South Africa are uncodified, and the civil law systems of Scandinavian countries remain largely uncodified.

The so-called Socialist law is often considered to be a particular case of the Romano-Germanic civil law, though in the past it was sometimes classified as a separate legal system.”

I would add too that commone law is so influential due to British colonialism and that with the civil law system you can get some very young judges as it is something that in certain countries you can get a certificate in .

In common law when a Judge interprets a new piece of legislation and makes a judgment he is then setting a precedent. This is an argument for the way a particular piece of law should be interpreted.

The Lord Chancellor who is known in history as the keeper of the king’s consciousness. This role in the medieval period was filled by clergyman, or other non lawyers.

In 1601 equity took precedent over common law.

What is equity Law?

Quote from Wikipedia

“Equity is the name given to the set of legal principles, in jurisdictions following the English common law tradition, which supplement strict rules of law where their application would operate harshly, so as to achieve what is sometimes referred to as "natural justice." It is often confusingly contrasted with "law", which in this context refers to "statutory law" (the laws enacted by a legislature, such as the United States Congress), and "common law" (the principles established by judges when they decide cases).”

Glanvill writing in about 1180 tell us that in his time “it is not custom of the court of the lord King to protect private agreements” three centuries were to pass before the common law courts acquired general jurisdiction over both formal and informal contacts.

Why is contract law so important, in medieval time it meant you could own land. If you could own land it gave you rights. The resolution system in this time was very primitive. It was enforced by royal courts. They were mainly concerned with murder, mayhem and the ability to raise arms.

Later on other courts developed, Courts of fairs and markets, Courts of pie powder, Country courts, courts of purchase, courts of universities.

A modern example of a market court would be to allow Benetton to sell its wares, now referred to as franchise law.

Pie Powder Courts were set up in small towns, villages, and ports throughout England during the Norman and Medieval period to preside over the goings on at Fairs, markets and seaports, abolished in 1865

Medieval contract actions has now become Torts (Interference with Goods Act 1977)

Medieval contracts were notated in documents with a wax seal. They required the wax seal to be legally binding. If there was a dispute it was solved by compurgation. Where the defendant swore under oath that he told the truth if he found eleven others who would support his oath he was a free man.

Rich people would employ Knights to battle it out. If the knight lost he could never fight again. Poor people just went to the common ground with sticks and beat each other in till one party gave up.

Penal Bonds - 1870

“So far as contracts under seal were concerned from the middle of the fourteenth century the action of the covenant came to be replaced by the action of debt based on a conditional bond” Quote from David Ibbetson

Penal bonds replaced action of convent. They would enter into a bond say I will pay to you the sum of X shillings if I fail to do this I will forfeit w

Assumpsit first appeared in 1367 in the Skyrne v Butolf case when the plaintiff sued a doctor with whom he had contract with to cure ringworm. This breach of contract become known as assumpsit. Assumpsit replaced sur contract which deprived the defendant of his right to wage law and force the other party to submit to trial by Jury. In 1611 it went one step further in the Pinchon’s Case where simple contract liability was passively transmissible.

By the eighteen century the principle had emerged that “equity suffers not advantage to be taken of a penalty or forfeiture where compensation can be made. This approach was soon widely adopted bringing to an end penalties in contracts.

In the seventeen century assumpsit develop into quasi-contract. Assumpsit which had been known as indebitatus (indebted to you). This meant that the details of the contract need only be set out in summary form. The defendant would be said to be indebted for the price of the goods or money lent etc.

The courts evolved a special form of assumpsit which was to be used to recover reasonable sums of money known as quantum meruit or quantum valebat this laid the foundation for the extensive use of the concept of an implied promise in English contract law.

The nineteen century is general regarded as the classical age of English contract law. Freedom of Contract a principle road to social improvement. As expressed by Sir George Jessel in printing and Numerical registering co v Sampson (1875)

“If there is one thing more than another which policy requires, it is that men of full age and competent understanding shall have the utmost liberty in contracting, and that their contracts when entered into freely and voluntarily, shall be held sacred and shall be enforced by courts of justice”